Finger-mounted filing device

ABSTRACT

A finger-mounted filing device can include an abrasive surface that can include a plurality of cutting edges in fixed relation. The abrasive surface can be used for grinding a work surface, such as a fingernail of an infant, child, or adult. The abrasive surface can include a finger surface located on an opposing face of the abrasive surface. The finger surface can be shaped to receive an operator&#39;s finger. The abrasive surface can be coupled to a finger clamp. The finger clamp can include the finger surface and at least one jaw, such as for griping an operator&#39;s finger. The finger surface can include a fingertip insertion stop. The fingertip insertion stop can include a barrier to retain the finger on the finger surface.

CLAIM OF PRIORITY

This patent application claims the benefit of priority of U.S. Provisional Patent Application Ser. No. 62/018,054 filed on Jun. 27, 2014, which is hereby incorporated by reference herein in its entirety.

BACKGROUND

Infants can produce self-inflicted injury as a result of their un-trimmed fingernails. Existing devices for trimming infant fingernails require one hand to hold the finger of the infant and the other hand to grip and control the trimming device. Some existing trimming devices employ clippers that can produce unintended cuts on the infant's finger, whereas others require batteries for operation. In addition, members of the general public, including amputees and those with impaired dexterity, can find it difficult to manipulate traditional manicuring nail files.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a finger-mounted filing device worn by an operator, according an example.

FIG. 2 illustrates a perspective view of a finger-mounted filing device according to an example.

FIG. 3 illustrates a perspective view of an abrasive surface including facets coupled to a finger-mounted filing device according to an example.

FIG. 4 illustrates a detailed view of cutting edges including abrasive granulate according to an example.

FIG. 5 illustrates a detailed view of cutting edges including teeth according to an example.

FIGS. 6A and 6B illustrate a perspective view and a side view, respectively, of a finger-mounted filing device with a two-section jaw configuration according to an example.

FIG. 7 illustrates a side view of a finger-mounted filing device with an unfaceted abrasive surface according to an example.

FIG. 8 illustrates a perspective view of a finger-mounted filing device including a two jaws and a semispherical fingertip insertion stop according to an example.

FIG. 9 illustrates a perspective view of a finger-mounted filing device with a single jaw according to an example.

FIG. 10 illustrates a flow chart of an example of a method for making a finger-mounted filing device according to an example.

DETAILED DESCRIPTION

Described herein are various configurations and designs for a filing device, such as a finger-mounted filing device for, in some instances, trimming fingernails. The following description and drawings sufficiently illustrate specific examples to enable those skilled in the art to practice them. Other examples may incorporate structural and other changes. Portions and features of some examples may be included in, or substituted for, those of other examples.

A finger-mounted filing device can include an abrasive surface, a finger surface, and a finger clamp. In one example, the finger-mounted filing device can include a fingertip insertion stop. The abrasive surface (e.g., described with regards to FIG. 1) can include a plurality of cutting edges in fixed relation. The abrasive surface can be used for grinding a work surface, such as fingernails. The abrasive surface can include a finger surface located on an opposing face. The finger surface can be shaped to receive an operator's finger. In addition, the finger surface can include an aperture end and a fingertip insertion stop end. The fingertip insertion stop can provide resistance to further insertion of a finger, such as to maintain a position of the finger on the finger surface. The abrasive surface can be coupled to a finger clamp, such as at the aperture end of the finger surface. The finger clamp can include the finger surface and at least one jaw for griping an operator's finger.

In an example, the abrasive surface can include at least one facet thereon. The at least one facet can provide a filing surface oriented in a plane that facilitates translation of the abrasion surface by the movement of the operator's finger, such as to grind the fingernail or other work piece with the abrasion surface. The at least one jaw can include an elongate member aligned between the jaw and the fingertip insertion stop. The elongate member can be coupled to the jaw. The jaw and the finger surface can provide a clamping force to a finger positioned there between. The finger surface can be sized to permit flexure of at least one of the operator's knuckles when worn by the operator.

In an example, the abrasive surface can be formed as an unfaceted surface. The abrasive surface can include a convex surface (convex when viewed from the abrasive surface side), such as a conical shape that is substantially symmetrical about the axis of the operator's finger. In a further example, two jaws can be coupled to the aperture end of the finger surface. The two jaws can clamp the operator's finger when the operator's finger is inserted into the finger-mounted filing device. In an example, the clamping force is generated by the deflection of the jaws, such as deflection caused by the insertion of the operator's finger.

FIG. 1 and FIG. 2 illustrate an example of a device 100A worn by an operator depicted in a perspective view and a perspective view of the device 100A respectively. The device 100A can include an abrasive surface 102A-B (references with prefix 102 are collectively referred to in this disclosure as abrasive surface 102), a finger surface 104 (see FIG. 2) on the opposing face of the abrasive surface, a finger clamp (including jaw 106A and elongate member 110), and a fingertip insertion stop 108A. The finger clamp can include opposing elements: such as a finger surface 104 and at least one jaw 106A. The opposing elements can grip an operator's finger 112, such as the jaw 106A can be deflected by the insertion of a finger 112 into the device 100A thereby producing a reaction force that clamps the finger 112 between the opposing finger surface 104 and the jaw 106A. The clamp can include an elongate member 110. The elongate member can be aligned between an aperture end 114 of the finger surface 104 and the fingertip insertion stop 108A. At least one end of the elongate member 110 can be supported by the jaw 106A. The elongate member 110 can grip the finger 112 along the length of the elongate member 110, such as to clamp the finger 112 between the finger surface 104 and the jaw 106A. The fingertip insertion stop 108A can be located on one end of the finger surface.

The abrasive surface 102 can include a plurality of cutting edges. The cutting edges can be arranged in fixed relation on the abrasive surface 102, such that the cutting edges maintain their location and orientation on the cutting surface. In one example, the cutting edges are formed on a rigid, abrasive surface 102. The operator can move the abrasive surface 102 against the work piece (e.g., a fingernail, tooth, animal's nail, wood), such as to remove material from the work piece by rubbing the cutting edges against the work piece. The abrasive surface can be sized and shaped to fit between the fingers of an infant, such as to file the fingernail of the infant without cutting the surrounding fingers (e.g., a finger surface 104 that is less than 5 centimeters in length projected along the direction of axis 116 and less than 3 centimeters wide in a direction projected along axis 118). The abrasive surface 102 optionally includes at least one facet. The facet can be a planar surface or a plurality of planar surfaces. The at least one facet can be oriented tangential to the operator's finger, such as tangential to the operator's finger pad. In an example, the abrasive surface can include a plurality of facets (e.g., 102A and 102B). The plurality of facets can intersect one another at one or more edges, such that the plurality of facets can be oriented in different planes, giving the operator multiple filing surfaces to grind the work piece. The plurality of facets can be used by the operator to grind a work piece that is located near the operator's fingertip (e.g., 102A), along the pad of the operator's finger 112, or along the side of the operator's finger 112 (e.g., 102B). The facets can be aligned at an angle 602 (see FIG. 6B) between fifteen degrees to forty-five degrees between adjacent facets. In an example, the abrasive surface 102 can include a channel. The channel can be located on the abrasive surface with one end near the fingertip insertion stop 108A and the other end near the aperture end 114 of the abrasive surface 102, such as primarily along the direction of axis 116. The channel can include a profile shape, such as a slightly concave shape (concave when viewed from the abrasive surface side) of the abrasive surface 102 or a semi-circular shape. In a further example, the abrasive surface 102 can include a ridge, such a raised surface on the abrasive surface 102 in a direction substantially perpendicular from the abrasive surface 102 (e.g., along axis 120).

The abrasive surface 102 can be fabricated from a polymer, such as Acrylonitrile Butadiene Styrene (ABS), polycarbonate, polyamide; or from materials, such as aluminum, steel, ceramic, or glass. The abrasive surface 102 can include cutting edges formed thereon. The cutting edges may be formed from a hard material, such as a material that is harder than the material of the work piece. In an example, the cutting edges include teeth that can be formed from aluminum, steel, ceramic, glass, carbide, or a polymer. In a further example, the cutting edges can include abrasive granulate, such as aluminum oxide, silicon carbide, alumina-zirconia, ceramic aluminum oxide, garnet, corundum, or other abrasives. The abrasive granulate can be bonded or sintered together or coated to a backing material (e.g., paper, cloth, or the substrate), such as emery paper. The abrasive granulate can be integrated into the abrasive surface 102, such as by adhesive, insert molding, or heat welding. The abrasive granulate or teeth can be sized and shaped for removing material (e.g., grinding, polishing, filing, or lapping), such as granulate or teeth with cutting edges ranging from five micrometers to two millimeters.

The finger surface 104 provides a distributed contact face for applying force to the abrasive surface 102, such as for rubbing the abrasive surface 102 against the work piece. The finger surface 104 can be located on the opposing face of the abrasive surface 102. The finger surface 104 can be generally concave, such as to position the finger 112 in a desired location on the finger surface 104 (e.g., the center of the finger surface 104). In an example, the finger surface 104 can have a semi-circular cross-section when cut normal to axis 116. Maintaining the finger 112 on or near the center of the finger surface 104 can improve the function of the clamp, such as by preventing the finger 112 from sliding out from between the jaw 106, elongate member 110 and the opposing finger surface 104.

The shape of the finger surface 104 (e.g., the concave shape) can allow finger pressure to be applied to the angled facets on the abrasive surface 102 (e.g., abrasive surface 102B, located alongside the finger 112). In a further example, the finger surface 104 can be shaped and sized to fit the contour of the operator's finger 112. The contoured shape can further prevent the finger 112 from sliding on the finger surface 104. Reducing the amount of sliding of the finger 112 on the finger surface 104 can allow the operator to transfer more force and energy from the motion of the finger 112 to the work piece. In an example, the finger surface 104 can be textured, such as to include a non-slip surface. The finger surface 104 can include an adhesive to inhibit the finger 112 from slipping on the finger surface 104. In an example, the finger surface 104 can be less than five-centimeters long to permit articulation of at least one of the operator's knuckles.

The finger clamp can include the finger surface 104 and a jaw 106A. The finger surface 104 and jaw 106A can be positioned on opposing sides of an operator's finger 112. The jaw 106A can be a cantilevered beam, such as having one end supported by the abrasive surface 102 and the other end unsupported. In an example, the jaw 106A can have one end supported by the abrasive surface 102 and the other end can be coupled to an elongate member. The clamp can be configured such that the jaw 106A is expandable (e.g., can deflect in a plurality of directions), such as along axis 120, along axis 118, or both. In an example, the elongate member can couple the free ends of a first and second jaw 106A, such as to form a single jaw 106A. In another example, the jaw 106A can be coupled to the abrasive surface 102 and the finger surface 104, such as formed from a single integrated component (e.g., an injection molded part) as shown in FIG. 1. The clamp can be fabricated from a polymer material, such as ABS, polycarbonate, polyamide; or from other materials, such as aluminum, steel, ceramic, or other. In an example, the jaw 106A can be fabricated from a different material than the finger surface 104, such as steel, aluminum, an elastomer, or polymer. The finger surface 104 can be mechanically attached to the jaw 106A, such as by insert molding or secured by a fastener, latch, or snap-fit. In an example, the finger surface 104 can be bonded to the jaw 106A, such as by adhesive. The operator can rub the abrasive surface 102 against the work piece by moving their finger 112 as a result of the filing device 100A being retained to the finger 112 by the clamp. An aperture 122 can be formed between the finger surface 104 and the jaw 106A. The operator can insert a finger 112 through the aperture 122, wherein the finger 112 can be retained to the filing device 100A by force applied to the finger 112 by the opposing finger surface 104 and the jaw 106A. The force applied to the finger 112 by the clamp can be produced by configuring the size of the aperture 122 between the finger surface 104 and the jaw 106A, such as by sizing the aperture 122 to be smaller than the size of the finger 112. For example, a finger 112 having a diameter of 1.5 centimeters would be suitably clamped by an ABS structure having an aperture size of 1.4 centimeters. The clamping force can be generated by the deflection of the jaw 106A produced by inserting the finger 112 through the aperture 122. The deflection can produce a reaction force that pinches the finger 112 between the finger surface 104 and the opposing jaw 106A. The size of the aperture 122 can be configured to permit the insertion of a variety of finger 112 sizes, while still generating a force for retaining the finger 112.

The fingertip insertion stop 108A can provide a means for retaining the finger 112 to the device 100. The fingertip insertion stop 108A can be configured to maintain the finger 112 on the finger surface 104. The fingertip insertion stop 108A can include a barrier that prevents the fingertip of the finger 112 from being inserted through the aperture end 114 of the finger surface 104 and beyond the opposite end of the finger surface 104 when thrust in a forward stroke. In an example, the fingertip insertion stop 108 can be a ridge, a cup, a post, or an edge. The fingertip insertion stop 108 can be configured to receive a fingertip, such as engage with the fingertip while permitting the fingernail of the operator to lay free from contact with the fingertip insertion stop 108.

The elongate member 110 can be included in the clamp. The elongate member 110 can be aligned between the jaw 106A and the fingertip insertion stop 108. The jaw 106A and the elongate member 110 can be positioned on one side of a finger 112, and the finger surface 104 can be positioned on the opposing side of the finger 112. The elongate member 110 can include a cantilevered beam shape with one end coupled to the jaw 106A and the other end unsupported and located near the fingertip insertion stop 108A. In an example, the elongate member 110 can include a serpentine shape, such as both ends of the elongate member are coupled to the jaw 106A and the middle of the elongate member 110 is located near the fingertip insertion stop 108A. A force is exerted on the finger 112 along the length of the elongate member 110, such as primarily along the trajectory of axis 120 towards the finger surface 104. The force can be exerted on the finger 112 at a location between the aperture end 114 and the fingertip insertion stop 108A (e.g., the force can be exerted by the elongate member 110 at a location of the elongate member nearest to the fingertip insertion stop 108A). In an example, the elongate member 110 can retain the tip of the finger 112 to the finger surface 104. The elongate member 110 can be sized and shaped to include a length of one to three centimeters and a height and width of 0.1-3.0 millimeters, such as to function as a flexible hinge. The elongate member can be deflected by finger 112. When the elongate member 110 is fixed in a deflected position, a strain in the elongate member 110 is produced. In an example, the strain on the elongate member 110 can be reduced by increasing the length of the elongate member 110. Permanent deformation of the elongate member 110 can be used to custom-size the device 100 to a finger 112. In an example, permanent deformation of the elongate member 110 can be avoided by reducing the strain on the elongate member 112. Reduced strain can also increase the number of cycles in which a finger can be inserted into the device 100A or permit larger deflections of the elongate member 110, such as to accommodate a large finger 112 size.

FIG. 3 illustrates a view of the device 100A having an abrasive surfaces 102A-D, each of which is faceted. The abrasive surface 102 can include a plurality of cutting edges in fixed relation. Each abrasive surface 102 can include cutting edges of the same or of different type, such as abrasive granulate 402 or filing teeth 502.

In an example, a facet (e.g., abrasive surface 102C) can include cutting edges formed from an abrasive granulate 402, such as emery, aluminum oxide, silicon carbide, garnet, corundum, or other abrasives as shown in FIG. 4. The abrasive granulate 402 can be bonded or sintered together or coated to a backing material (e.g., paper, cloth), such as emery paper. The cutting edges can be integrated into to the abrasive surface 102, such as by adhesive, insert molding, heat welding, or ultrasonic welding. In an example, the abrasive granulate 402 can be integrated into the abrasive surface 102 in a substantially uniform thickness. The abrasive granulate 402 can be located uniformly on the abrasive surface 102, selectively located on portions of the abrasive surface 102, or on selective facets (e.g., 102 A-D). In an example, the abrasive granulate 402 can be arranged in a randomized pattern.

In a further example, a facet (e.g., 102D) of the abrasive surface 102 can include cutting edges, such as teeth 502 (as shown in FIG. 5) that can be formed on the facet from aluminum, steel, ceramic, glass, carbide, or a polymer. The teeth 502 can be arranged in a linear pattern on the abrasive surface 102, such as to be configured to remove material from a work piece when rubbed against the work piece in a particular direction. The teeth 502 can be oriented in different directions. In an example, each facet can include teeth 502 configured to remove material from a work piece when rubbed against the work piece in a different direction.

FIG. 6A and FIG. 6B illustrate a perspective view and a side view, respectively, of a device 100B with a jaw 106B configuration according to an example. The jaw 106B can be coupled to the abrasive surface 102 (e.g., 102A and 102B) in a location between the aperture 122 and the fingertip insertion stop 108A. The length L (e.g., the combined length of L1 and L2 collectively referred to as L) of the jaw 106B can be extended by selecting the location at which the jaw 106B is coupled to the abrasive surface 102. An extended length L of the jaw 106B can reduce the strain on the jaw 106B (e.g., strain applied to the jaw 106B as a result of the deflection of the jaw 106B when a finger 112 is inserted into the aperture 122), such as to lower the force applied to the finger 112 by the jaw 106B

In an example, the jaw 106B can include a cantilevered beam configured to deflect in more than one direction, such that a jaw 106B that can deflect in a direction away from the finger surface 104 (e.g., along axis 120 shown in FIG. 2.) and additionally outwards along axis 118 (shown in FIG. 2), for example, when a finger 112 is inserted through the aperture 122. The jaw 106B can include one or more sections, such as two sections as shown in FIGS. 6A and 6B. A first section (e.g., with length L1) aligned substantially along the direction of axis 116 and a second section (e.g., with length L2) aligned substantially along the direction of axis 120 as shown in FIG. 6B. The length L of the jaw 106B can be increased, without increasing the aperture 122 size, by coupling the jaw 106B to the abrasive surface 102 in a location between the aperture end 114 and the fingertip insertion stop 108A.

The abrasive surface 102 optionally includes at least one facet. The facet can be a planar surface or a plurality of planar surfaces. The at least one facet can be oriented tangential to the operator's finger, such as tangential to the operator's finger pad (e.g., abrasive surface 102B). In an example, the abrasive surface can include a plurality of facets (e.g., 102A and 102B). The plurality of facets can intersect one another at one or more edges, such that the plurality of facets can be oriented in different planes, giving the operator multiple filing surfaces to grind the work piece. The facets can be aligned at an angle 602 between fifteen degrees to forty-five degrees between adjacent facets (e.g., abrasive surfaces 102A and 102B).

FIG. 7 illustrates a side view of a device 100C with an abrasive surface 102E without facets according to an example. The abrasive surface 102 can include a convex shape, such as abrasive surface 102E. The convex shape of abrasive surface 102E can include cutting edges positioned on the exterior of the abrasive surface 102, such as cutting edges oriented in a plurality of directions. The operator can remove material from a work piece by rubbing the abrasive surface 102 against the work piece in a plurality of directions as described in other examples.

FIG. 8 illustrates a perspective view of a device 100D that includes an abrasive surface 102F, a first jaw 106C, second jaw 106D, a finger surface 104, and a fingertip insertion stop 108B. The first jaw 106C and the second jaw 106D are coupled to the abrasive surface 102F at one end, such as at the aperture end 114 of the abrasive surface 102F. In an example, the first jaw 106C and the second jaw 106D can be cantilevered, such that an end of the first jaw 106C and an end of the second jaw 106D are unconstrained. The first jaw 106C and the second jaw 106D can be deflected by the insertion of a finger 112 into the aperture 122. The first jaw 106C and the second jaw 106D can apply a reaction force to the finger 112 when deflected.

The abrasive surface 102F can be substantially convex on the exterior surface. The abrasive surface 102F can include abrasive granulate or cutting teeth (as described in relation to other examples) that are located on the abrasive surface 102F, the first jaw 106C, the second jaw 106D, or the fingertip insertion stop 108B. The abrasive surface can include a semi-circular cross-section cut normal to axis 116.

The device 100D can include a fingertip insertion stop 108B, such as a fingertip insertion stop with a semispherical shape. The fingertip insertion stop 108B can be concave on the interior finger surface 104, such as to inhibit a finger 112 from sliding on the finger surface 104 beyond the fingertip insertion stop 108B.

FIG. 9 illustrates a perspective view of a device 100E with one jaw 106E according to an example. The device 100E can include a jaw 106E and an abrasive surface 102F, finger surface 104, and fingertip insertion stop 108B as previously described in FIG. 8. The jaw 106E can include a semi-circular shape. The first end and the second end of the jaw 106E can be coupled to the abrasive surface 102F. In an example, the jaw 106E can be coupled to the abrasive surface at an aperture end 114 of the finger surface 104.

The jaw 106E can be configured to deflect when a finger 112 is inserted into the aperture end 114. In an example, the operator's finger 112 can compress so the finger 112 can be inserted into the aperture 122. The jaw 106E can optionally be formed from an elastomeric material. The elastomeric material can be natural or synthetic rubber, or a thermoplastic elastomer. The elastomeric jaw 106E can be coupled to the abrasive surface 102F by a fastener or can be retained to the abrasive surface 102F by weaving the elastomer through one or more eyelets included in the abrasive surface 102F.

FIG. 10 illustrates a flow chart of an example of a method 1000 for making a device 100A according to an example.

At 1002, the method 1000 can include forming a plurality of cutting edges on an abrasive surface 102 in fixed relation. The cutting edges can be formed on a rigid surface, such as fixing the relation of the cutting edges. The abrasive surface 102 can include cutting edges formed from a harder material than the work piece material. In an example, the abrasive surface 102 can be fabricated from a polymer, such as ABS, polycarbonate, polyamide; or from other materials, such as aluminum, steel, ceramic, or glass. The cutting edges can include abrasive granulate 402, such as emery, aluminum oxide, silicon carbide, garnet, corundum, or other abrasives. The abrasive granulate 402 can be bonded or sintered together or coated to a backing material (e.g., paper, cloth, or the substrate), such as emery paper. The Abrasive granulate 402 can be integrated into the abrasive surface 102, such as by adhesive, insert molding, or heat welding. The abrasive granulate 402 can be integrated into the abrasive surface 102 in a substantially uniform thickness. In a further example, the abrasive granulate 402 can be arranged in a randomized pattern. The abrasive granulate 402 can be located uniformly on the abrasive surface 102, selectively located on portions of the abrasive surface 102, or on selective facets (e.g., 102 A-D).

In another example, the abrasive surface 102 can include cutting edges, such as teeth 502 that can be formed from aluminum, steel, ceramic, glass, carbide, or a polymer. The cutting edges can be formed on the abrasive surface 102. In an example, the cutting edges can be located uniformly on the abrasive surface 102, selectively located on portions of the abrasive surface 102, or on selective facets (e.g., 102 A-D).

At 1004, the method 1000 can include providing a finger surface 104 on an opposing surface of the abrasive surface 102. The finger surface 104 can be configured to have a distributed contact face for applying force to the abrasive surface 102. The finger surface 104 can be generally concave from the internal side (finger 112 side), such as to position the finger 112 in a desired location on the finger surface 104 (e.g., the center of the finger surface 104). In an example, the finger surface 104 can have a semi-circular cross-section when cut normal to axis 116. The finger surface 104 can be less than five-centimeters long to permit articulation of at least one of the operator's knuckles. In an example, the finger surface 104 can be shaped and sized to fit the contour of the operator's finger 112. In a further example, the finger surface 104 can be textured, such as to include a non-slip surface. The finger surface 104 can include an adhesive to inhibit the finger 112 from slipping on the finger surface 104.

At 1006, the method 1000 can further include coupling a finger clamp to the abrasive surface 102, the finger clamp including the finger surface 104 and a jaw 106(e.g., 106A-E). The finger surface 104 and jaw 106 can be positioned on opposing sides of the aperture 122. The size of the aperture 122 between the finger surface 104 and the jaw 106 can be configured to be smaller than the size of a finger 112. In an example, the size of the aperture 122 can be configured to permit the insertion of a variety of finger 112 sizes, while still generating a force for retaining the finger 112. The jaw 106 can be formed as a cantilevered beam, such as having one end supported by the abrasive surface 102 and the other unsupported. In an example, the jaw 106 can have one end supported by the abrasive surface 102 and the other end can be coupled to an elongate member 110. The jaw 106 can be coupled to the abrasive surface 102 and the finger surface 104, such as formed from a single integrated component as shown in FIG. 1. The clamp can be fabricated from a polymer material, such as ABS, polycarbonate, polyamide; or from other materials, such as aluminum, steel, ceramic, or other. In an example, the jaw 106 can be fabricated from a different material than the finger surface 104, such as steel, aluminum, an elastomer, or polymer. Alternatively, the abrasive surface 102 and the finger surface 104 can be mechanically attached to the jaw106, such as by insert molding or secured by a fastener, latch, or snap-fit. In an example, the abrasive surface 102 and the finger surface 104 can be bonded to the jaw 106, such as by adhesive.

An elongate member 110 can be coupled to the jaw 106, such as formed thereon. The elongate member can be aligned between the jaw 106 and the fingertip insertion stop 108. The elongate member 110 can include a cantilevered beam shape with one end coupled to the jaw 106A and the other end unsupported and located near the fingertip insertion stop 108A. In an example, the elongate member 110 can include a serpentine shape, such as both ends of the elongate member are coupled to the jaw 106A and the middle of the elongate member 110 is located near the fingertip insertion stop 108A. A force is exerted on the finger 112 along the length of the elongate member 110, such as primarily along the trajectory of axis 120 towards the finger surface 104. The force can be exerted on the finger 112 at a location between the aperture end 114 and the fingertip insertion stop 108A (e.g., the force can be exerted by the elongate member 110 at a location of the elongate member nearest to the fingertip insertion stop 108A). In an example, the elongate member 110 can retain the tip of the finger 112 to the finger surface 104. The elongate member 110 can be sized and shaped to include a length of one to three centimeters and a height and width of 0.1-3.0 millimeters, such as to function as a flexible hinge. In an example, the strain on the elongate member 110 can be reduced by increasing the length of the elongate member 110. In an example, permanent deformation of the elongate member 110 can be used to custom-size the device 100 to a finger 112. In an example, permanent deformation of the elongate member 110 can be avoided by reducing the strain on the elongate member 112. Reduced strain can also increase the number of cycles in which a finger can be inserted into the device 100A or permit larger deflections of the elongate member 110, such as to accommodate a large finger 112 size.

The method 1000 can optionally further include: forming a fingertip insertion stop 108 located at an end of the finger surface 104 opposite to an aperture end 114 of the finger surface 104. The fingertip insertion stop 108 (e.g., 108A or 108B) can include a barrier that prevents the fingertip of the finger 112 from being inserted through the aperture end 114 of the finger surface 104 and beyond the opposite end of the finger surface 104. In an example, the fingertip insertion stop 108 can be a ridge, a cup, a post, or an edge. The fingertip insertion stop 108 can be configured to receive a fingertip, such as engage with the fingertip while permitting the fingernail of the operator to lay free from contact with the fingertip insertion stop 108.

The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein. In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls.

In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. 

What is claimed is:
 1. A device comprising: an abrasive surface, wherein the abrasive surface includes a plurality of cutting edges in fixed relation; a finger surface on an opposing face of the abrasive surface; and a finger clamp coupled to the abrasive surface, the finger clamp including the finger surface and a jaw.
 2. The device of claim 1, further comprising a fingertip insertion stop located at an end of the finger surface opposite to an aperture end of the finger surface.
 3. The device of claim 1, wherein the abrasive surface includes at least one facet.
 4. The device of claim 3, wherein at least two facets are aligned at an angle between fifteen degrees to forty-five degrees.
 5. The device of claim 1, wherein the jaw includes a cantilevered beam.
 6. The device of claim 5, wherein the jaw includes an elongate member, the elongate member aligned between the jaw and the fingertip insertion stop.
 7. The device of claim 1, wherein the finger surface has a length of less than five-centimeters.
 8. The device of claim 1, wherein the finger surface has a concave shape.
 9. A method comprising: forming a plurality of cutting edges on an abrasive surface in fixed relation; providing a finger surface on an opposing surface of the abrasive surface; and coupling a finger clamp to the abrasive surface, the finger clamp including the finger surface and a jaw.
 10. The method of claim 9, further comprising forming a fingertip insertion stop located at an end of the finger surface opposite to an aperture end of the finger surface.
 11. The method of claim 9, further comprising providing at least one facet on the abrasive surface.
 12. The method of claim 11, further comprising aligning at least two facets at an angle between fifteen degrees to forty-five degrees.
 13. The method of claim 9, further comprising forming a cantilevered beam on the jaw.
 14. The method of claim 13, further comprising forming an elongate member on the jaw, the elongate member aligned between the jaw and the fingertip insertion stop.
 15. The method of claim 9, further comprising configuring the finger surface to have a length less than five-centimeters.
 16. The method of claim 9, further comprising contouring the finger surface to have a concave shape. 